1.HY-2A scatterometer data
In this paper, HY-2A data were downloaded via FTP service(ftp2.nsoas.org.cn) with registriation permission, which can be accessed from National Satellite Ocean Application Service(NSOAS:http://www.nsoas.org.cn/eng/).
Since HY-2A/SCAT dataset are stoppted to be distrubted, for convenience, we have uploaded the ASCII file of HY-2A scatterometer data which were converted from the oringnal HDF5 files of HY-2A/SCAT. 
The ASCII files contain all the data we used in this study with no more operations of the original files.
The parameters ,"#lat, lon, year, month, day, hour, minute, w_spd, w_dir, mle, qcflag, m_spd, m_dir, wvc" , in ASCII files represent
scatterometer lat, scatterometer lon, scatterometer observation time, scatterometer wind speed (m/s), scatterometer wind direction (degree in oceanological convention), 
scatterometer model wind speed (m/s), scatterometer model wind direction (degree), and scatterometer wind vector cells, respectively.

2. HY-2B scatterometer data and CFOSAT scatterometer data
HY-2B/SCAT and CFOSCAT data were downloaded from website：https://osdds.nsoas.org.cn/#/?lang=en.
People who are interested in these data should register first and then select the interested time periods and instruments to download the data. 

3.ECMWF MARS buoy data
Buoy data we used were downloaded from ECMWF MARS. Several steps and softwares should be taken to access the data.
People who want to download this buoy data should install PenWP software first, which can be accessed from https://nwp-saf.eumetsat.int/site/software/scatterometer/penwp/
The folder "buoyread" we uploaded should be put into the path "genscat/tools" and compile the whole software.
Detailed downloading method is introduced in Readme.txt under buoyread folder.

4.collocation dataset
For convenience, we also uploaded the collocation dataset we used in this study. 
The data file named with "all" represent the collocation data that contain all offshore collocation data and were processed by quality control.
The data file named with "neutral" represent the offshore collocation dataset under neutral stratification conditions.
The data file named with "stable" represent the offshore collocation dataset under stable stratification conditions.
The data file named with "unstable" represent the offshore collocation dataset under unstable stratification conditions.
In these files, the parameters "#Buoy    Lat     Lon      Date Time Speed   Dir Scat Lat     Lon      Date Time Speed   Dir  MSpd  MDir WVC    Alfa     MLE"  represent
buoy station ID, buoy lat, buoy lon, buoy observation time, 10 m buoy stress-equivalent wind speed (m/s), buoy wind direction (degree in meteorological convention),
scatterometer lat, scatterometer lon, scatterometer observation time, scatterometer wind speed(m/s), scatterometer wind direction(degree in meteorological convention), 
scatterometer model wind speed(m/s), scatterometer model wind direction(degree in meteorological convention),
scatterometer wind vector cell numbers, satellite direction of flight, and scatterometer Maximum Likelihood Estimator values, respectively.
Number 999.00 or -999.00 means invalid values.
Detailed collocation methods and quality control steps are introduced in the section 2.5 of our paper.